We need to think carefully before we overreact to reports of online child abuse, argues technology analyst Bill Thompson.

Just as it is impossible to be completely accurate about how many people actually use the internet around the world, or how many people are writing weblogs, so it is impossible to get comprehensive figures about the ways the net is used for illegal activities.

We know that there are fraudsters, criminals and child abusers out there, but we cannot know how many or exactly where they are.

For that reason, I am doubtful about the usefulness of the UK's National Criminal Intelligence Service telling people that the number of websites showing images of child sexual abuse has doubled in the last year.

It makes good headlines, and it gets them more coverage of their annual assessment of what organised criminals are up to both online and offline, but I am not sure it helps us as we try to decide what to do about this serious problem.

Instead it is more likely to create a sense of panic, and persuade unthinking campaigners and compliant politicians to call for some sort of clampdown on the net - a clampdown that will affect us all.

Technologically sophisticated

The report on the scale of the increase seems to come from the Internet Watch Foundation, which operates a public hotline where people can report sites with images of child abuse.

However images which people find on publicly accessible websites are only ever going to make up a tiny proportion of the total, and the increase can just as easily be accounted for by improved public awareness of the problem rather than an actual increase in the number of sites or images.

Part of the problem is that we are too keen to think that crimes which involve the internet are seen as internet crimes and must be dealt with by controlling the net

It is unfortunate -if predictable - that attention has focused on this one number, because the NCIS report contains a useful analysis of the ways that the net is being used by paedophiles and those who seek out images of child abuse.

It makes clear that many of them are technologically sophisticated and able to take advantage of the net's ability to disguise information when it is being sent from place to place, or to limit access to websites and chat rooms to approved users.

These people have created complex, hierarchical organisations which they believe can keep them safe from discovery. Like any online community, they are not forced to meet in person, and they are aware of the surveillance and monitoring techniques used by law enforcement agencies.

And like any group of technically adept users, they are perfectly capable of adapting their behaviour or using new technologies as they become available.

For example, there are indications that peer-to-peer networks, designed to avoid snooping by copyright holders, are being adopted by those who want to trade images of child abuse and who want to avoid snooping by the police.

The real world

We can draw two useful lessons from this sort of information.

First, simple-minded measures to restrict our online freedoms will not be effective at limiting the use of the net by those who abuse children or who seek to make money out of this sort of abuse.

It is pointless to try to restrict the use of encryption tools by ordinary net users, because the criminals and abusers already have access to this technology and will quickly adopt any new developments to improve their own security.

Second, it is almost certainly better to attempt to infiltrate these organisations than to attempt to break their security measures.

After the attacks on the US in September 2001, it became clear that the US intelligence agencies had too few agents on the ground, inside the communities from which al-Qaeda was recruiting, and had relied too much on intercepted communications and computer analyses.

We should try to avoid this mistake in investigating groups which trade images of abuse.

Part of the problem is that we are too keen to think that crimes which involve the internet are seen as internet crimes and must be dealt with by controlling the net.

Instead of worrying just about the internet, we should be considering how best to equip the police to investigate these crimes, what resources they need to infiltrate these criminal organisations, and how to ensure that they do so while respecting the civil rights of everyone else.

It is time to stop treating the network as special, and to recognise that the internet is part of the real world, just like television, roads and money. Otherwise we will both fail to solve the real problems and end up limiting the net's potential to transform our lives.

Bill Thompson is a regular commentator on the BBC World Service programme Go Digital.